Suggest you either open a separate thread or even better open a ticket at support.zend.com.

since the thread was opened, we have released a few versions (latest being ZS 8.5.2) and you are certainly encouraged to install the latest.
If you do open a forum thread rather than a support ticket, then please add there which OS+distro you're using, and what was the installation flow (clean / upgrade, did you use repo installer or command line command, etc..)